Are there any USB DACs out there that work with the native volume controls in MacOS (and windows I guess)
Most of the ones I’ve used have a knob on the front that controls the volume, and you can’t use the keyboard buttons to change it. It’s not the worst thing in the world but kind of annoying.
Or look for battery powered dacs with no volume knob, or the Audioquest Dragonfly.
Make sure you’ve selected the usb dac in sound output, may be a radio button for onboard volume.